Bi_2O_3-Y_2O_3系阻抗谱研究

AC COMPLEX IMPEDANCE STUDY ON SOLID STATE ELECTROLYTE OF Bi_2O_3-Y_2O_3

本文用交流阻抗法研究了Bi_2O_3-Y_2O_3系的阻抗谱。呈现特有的Warburg阻抗及其相关阻抗。在高氧分压下,电极过程由氧原子在三相线发生反应后直接进入电解质步骤控制;低氧分压下,由上述步骤和界面浓差极化共同控制,或仅由浓差极化控制。在氧分压为1.01×10^(-10)～1.01×10~5Pa内时,Bi_2O_3-Y_2O_3系表现为纯氧离子导体。

Complex impedance diagram on Bi_2O_3-Y_2O_3 system was investigated using AC impedance method. It was found that Ba_2O_3-based materials are characteristic of the Warburg impedance. The rate-limiting step of the electrode process at high Po_2 is the diffussion of oxygen atom into the solid electrolyte on the triple line. At low Po_2 the electrode process is controlled by diffusson as well as by concentration polarization, or controlled only by concentration polarization. Ba_2O_3-Y_2O_3 system characterized as a pure oxygen icn conductor at Po_2=1×1^(-10)～1×10~5Pa